The conversion of a dormant bacterial (Bacillus) spore into a vegetative bacterium by the process of spore germination is a relatively simple differentiating system which is readily amenable to biochemical analysis. A major feature of this differentiation process is extensive and rapid hydrolysis of spore protein. Degradative enzymes are important in regulating enzyme levels especially in mammalian cells, and in several processes including bacterial sporulation, yeast budding, and sea urchin egg development. Therefore, investigation of the role of degradative enzymes in spore germination may provide insights into the control of differentiation in higher organisms. The objective of this project is the elucidation of the mechanism of action and the function of proteolytic enzymes in the germination of bacterial spores - especially with regard to potential control functions. Specific aims are to: 1) complete the amino acid sequence analysis of the unique low molecular weight spore proteins degraded during spore germination; 2) complete the determination of the amino acid sequence specificity of the spore protease responsible for the initiation of degradation of the unique low molecular spore proteins; 3) purify and characterize a newly identified group of spore proteins which are also degraded during spore germination; 4) characterize the now homogeneous spore protease with regard to its physical and enzymatic properties; 5) determine the intrasporal location of both the protease and its substrate(s); 6) elucidate possible regulation of the spore protease via inhibitors and/or covalent modification including its possible synthesis as a zymogen; 7) identify the site of synthesis of both the spore protease and its low molecular substrates during sporulaion - is this the mother cell or the developing forespore?; and 8) analyze and characterize recently obtained mutants lacking the unique spore protease to determine (a) the function of the protease and (b) the role(s) of its protein substrates in the dormant and germinating spore.